So you want more ammo in order to get the vehicle for nothing?
Well, there is another answer, however it isn't free. I would recommend using this website regardless of what you are buying (provided it's a new vehicle), in addition to your ad's so that you know exactly what the dealer has into the vehicle. What's the website?
Car Cost Canada
This website will give you a detailed run down of the dealer msrp, invoice, holdback, financing & lease rates as well as the dealer incentives and kickbacks. Does it work for the USA? I have no idea! However, when buying a car in Canada, this tool is amazing.
Pick your vehicle.
Print off the Car Cost Canada report.
Bring it with you and buy your vehicle for practically nothing.